ASTM A572 Gr 50 Steel Plates
Grade 50 is a high strength, low alloy steel that finds its best application where there is need for more strength per unit of weight. Less of this material is needed to fulfill given strength requirements than is necessary with regular carbon steels. Grade 50 is used in general plate applications when the plate will be riveted, bolted, or welded. Grade 50 is a Columbium-Vanadium steel that offers a minimum yield of 50,000 PSI. In addition, ASTM A572 Grade 50 is noted for its increased resistance to atmospheric corrosion. Grade 50 contains more alloying elements than plain carbon steel and thus is somewhat more difficult to form. Grade 50 is more difficult to cold work, but can be successfully bent or shaped but requires more force than plain carbon steel.

ANALYSIS

Carbon (C)

Manganese (Mn)

Silicon (Si)

Vanadium (V)

Niobium (Nb)

Phosphorus (P)

Sulfur (S)

Over 1-1/2"

0.23

1.35

0.15-0.4

0.01-0.05

0.005-0.05

0.04

0.05

Up to 1-1/2"

0.23

1.35

0.4

0.01-0.05

0.005-0.05

0.04

0.05

Grade 50 conforms to ASTM A572

MECHANICAL PROPERTIES

Tensile Strength (PSI)

Yield Strength (PSI)

Elongation in 2"

Brinell Hardness

65,000

50,000

19

135

The above values are average and may be considered as representative of ASTM A572 Grade 50 Elongation in 8": 16%

APPLICATIONS

ASTM A572 Grade 50 is considered a "workhorse" grade and is widely used in many applications. Steel mills produce channel and heavy beams with Grade 50. It is commonly used in structural applications, heavy construction equipment, building structures, heavy duty anchoring systems, truck frames, poles, liners, conveyors, boom sections, structural steel shapes, and applications that require high strength per weight ratio.

MACHINEABILITY AND WELDABILITY

Machinability is rated at 66% of B1112. Average cutting speed 110 ft/min. Easily welded by all commercial methods.

HEAT TREATING

Grade 50 is generally used in the "as supplied" condition. Annealing, if required, can be done at 1700° F and slow furnace cooled.

TOLERANCES

Tolerance Over Specified Thickness, For Widths Given, in Inches

Thickness (Inches)

Thru 47"

48 to 59"

60 to 71"

72 to 83"

84 to 95"

96 to 107"

108 to 119"

120 to 131"

132 to 143"

144 to 167"

To under 1/4

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.04

-

1/4 to under 5/16

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.04

0.04

-

5/16 to under 3/8

0.03

0.03

0.03

0.03

0.03

0.03

0.03

0.04

0.04

0.05

3/8 to under 5/8

0.03

0.03

0.03

0.03

0.03

0.03

0.04

0.04

0.05

0.06

3/4 to under 1

0.03

0.03

0.03

0.03

0.04

0.04

0.05

0.05

0.06

0.07

1 to under 2

0.06

0.06

0.06

0.06

0.06

0.07

0.08

0.10

0.10

0.11

2 to under 3

0.09

0.09

0.09

0.10

0.10

0.11

0.12

0.13

0.14

0.15

3 to under 4

0.11

0.11

0.11

0.11

0.11

0.13

0.14

0.14

0.14

0.15

4 to under 6

0.15

0.15

0.15

0.15

0.15

0.15

0.15

0.15

0.15

0.20

Tolerance under specified thickness .010". A 3/4 x 52" wide plate, for example, would have a tolerance range of .740/.780"
Because of tolerances, i.e. thickness, flatness and camber, as well as the hot roll condition, ASTM A572 Grade 50 generally does not finish to specified thickness.
CAMBER Permissible Camber for sheared and Gas-Cut ASTM A572 Grade 50 Plate, All Thicknesses

Number of feet of length
Maximum Camber, Inches = 1/8" X ( Number of feet of length/5)

FLATNESS For all plates, the longest dimension is considered the length, and flatness tolerance along the length should not exceed the amounts indicated below the specified width and thickness in plate though 12' in length or longer. The flatness variations across the width should not exceed the tabular amount for the specified width.
Flatness Tolerances For Specified Widths, in Inches
(Maximum deviation from a horizontal flat surface)